Leveling bridge



April 22, 1952 w. H. BOTHE ET AL LEVELING BRIDGE Filed Feb. 28, 1951 3. m i m Q. F m U m Patented Apr. 22, 1952 FF ICE LEVELING BRIDGE Werner H. Bathe, Kenosha, and Herman J. Miller, Cudahy, Wis., assignors to Worldsbest Industries, Ino., Cudahy, Wis., a corperation of Wisconsin Application February 28, 1951, Serial No. 213,674

2 Claims.

This invention relates to stretching frames for use in drying curtains and other fabrics.

The object .of the invention is to provide a levelling bridge for stretching frames and more particularly to provide certain improvements over the levelling bridge shown and described in the copending application Serial No. 172,954, filed July 10, 1950, of Werner H. Bothe, for Levelling Bridge. In said application, the bridge structure is clamped to the adjusting bar or post by a clamp which extends laterally from the front side of this bar, and this has been found objectionable because it limits the available stretching length of the frame since some clearance has to be allowed between said adjusting bar and the unpinned end bar of the frame in order to manipulate the clamp. One of the objects of the present invention is to eliminate the above mentioned objection by providing bridge clamping means which act to clamp the pin carrying bridge plate to the back side of said adjusting bar by exerting a clamping pressure on the front side of the bar.

A further object of the invention is to provide a levelling bridge in which the bridge member itself under the action of the bridge clamp holding it to the adjusting bar also exerts a clamping pressure upon the bottom bar through the leverage action of the pivoted bridge member.

The invention further consists in the several features hereinafter set forth and more particularly defined by claims at the conclusion hereof.

In the drawings:

Fig. 1 is a plan view of a levelling bridge structure embodying the invention showing it applied to a stretching frame;

Fig. 2is a vertical sectional view taken on the line 2-2 of Fig. 1, parts being broken away;

Fig. 3 is a vertical sectional view taken on the line 33 of Fig; 1;

Fig. 4 is a view similar to Fig. 1 showing certain modifications; I

Fig. 5 is a sectionalview taken on the line 5-5 of Fig. 4.

In stretching frames in which the curtains or other fabric to be dried are impaled on pins mounted in some of the frame members, the socalled vertical adjusting bar or post 6 provided with pins I forms a frame corner with the horizontal rail or bar 8 overlying the bar 6 and provided with pins 9, said bar 8 being adjustably clamped to the left hand end bar or post and also to the bar 6 by suitable clamping means. As herein shown, a U-shaped clamping member ID straddling the bar 6 carries a threaded rod f of the levelling bridge.

or bolt H provided with a clamping nut l2, and an angled clamping member !3 apertured to receive the rod i I is brought into engagement with both bars 6 and 8 when the nut 12 is clamped down against its top leg it, a spring 15 being interposed between the members ill and I3 to facilitate release of these members when the nut I2 is loosened. With the bars 6 and 8' clampedimposition as above described the sets of pins 1 and 9 are vertically spaced from each other at the corner joint formed between these bars so that ordinarily the pins 7 adjacent the bar Bare not eifective to hold the fabricbeing stretched and to provide an effective pinning area at this part of the frame a pin carrying leveling bridge is used.

In each of the forms shown herein, a levelling bridge comprises a pin carrying plate [6 in the form of an angled plate having one side H extending parallel to the bar 6 and its other side. formed to provide spaced ears or projections l8; in each of which the shank of a pin I9 is. anchored, the disposition of the pins I9 being,

such that when the side I! of said plate is brought into close or abutting relation with the front edge of the bar 6, the pins [9 will be alined with the pins 1, and some of these pins l9 will be disposed between some of the pins I as shown in the drawings, and both sets of pins l9 and I are functioning together for a portion of the length The levelling bridge I6 is secured in each instance to the bar 6 by clamping means in the form of a channel member 20,

one of whose legs or sides Zea has the bridge l6 pivotally connected thereto, intermediate its ends, by a pin 2| and the ot er of whose legs or sides 20b has an angled top extension 22. The squared portion at the head end of a carriage bolt 23 is mounted in a square hole 24 in said extension to prevent relative rotary movement and carries a clamping nut 25. A U-shaped clamping plate 26 provided with feet 21 straddles the extension 22 and has a hole 28 through which the threaded shank of the bolt 23 is slidably mounted. The nut 25 bears against the bridge portion of the plate, and on being tightened 7 moves the feet 21 down against the top portion of the bar 6 and pulls up on the head of the bolt 28 and through it draws the base of the channel 20 against the under side of the bar 6, thus tightly clamping the bridge It to the bar 6, and as the wing nut 25 is disposed over the front face of the bar 6, it does not interfere with the lateral adjustment of this bar to a position adjacent the right hand post (not shown) of the stretching frame, so that the range of adjustment of this bar is not curtailed as in the aforementioned application. A spring 29 is interposed between the extension 22 and the member 26 to facilitate release of the clamping means. In the form shown in Figs. 4 and 5 the bridge member I6 is similar to that of the application above referred to and is adapted in its operative position to abut the front edge of the bar 8.

The bridge member I6, shown in Figs. 1 and 2, has a tongue or finger 3| which when the bridge is in position engages over the rabbeted front face 3| of the bar 8 and exerts a clamping pressure on this bar as it is clamped to the bar 6, and this is the preferred construction. With this construction as the channel member 20 is pulled up against the bottom of the bar 6, the clamping.

pressure exerted on the extension 22 tends to cant the leg 20a outwardly from said bar 6, thus moving the pivot 2] and finger carrying end of the bridge downwardly or toward the bottom of the bar 8 to grip the finger 38 with said bar 8 if the parts are correctly positioned relative to each other, but even if they are not so positioned that said finger 30 does not actually grip the bar 8, it will still act as a stop to prevent downward movement of the finger carrying part. of the bridge relative to the bar 8 under the action of stretching pressures applied to the pins l9 by the fabrics being stretched.

We desire it to be understood that this invention is not to be limited to any particular form or arrangement of parts except in so far as such limitations are included in the claims.

What we claim as our invention is:

1. In a stretching frame having angularly disposed and joined pin carrying frame members with one of said frame members overlying the other frame member, the combination of a channel supporting member extending around the bottom and sides of the underlying frame memher, a pin carrying levelling bridge carried on one side of the leg of said channel member disposed adjacent the front side of said underlying frame member, the other leg of said channel member having an angled extension overlying the front face of said underlying frame member, a clamping member distinct from said bridge and engageable with the front face of said underlying frame member adjacent said extension, and means connected with said angled extension for drawing said clamping member and the bridge portion of said channel member into clamping engagement with said underlying frame member to clamp said levelling bridge in position at the joint between said members to provide an inclined pinning path between pins of said frame members.

2. The structure as defined in claim 1 in which the levelling bridge is pivotally connected intermediate its ends to the aforementioned leg of said channel supporting member for swinging movement in a plane substantially parallel to the front side of said underlying frame member.

WERNER H. BOTHE. HERMAN J. MILLER.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,929,629 Daugherty Get. 10, 1933 2,217,004 Carlson Oct. 8, 1940 2,448,574 Bethe Sept. 7, 1948 2,496,645 Unwin Feb. '7, 1950 

